Diastereoselective rhodium(II)-catalyzed sulfonium ylide formation-[2,3]-sigmatropic rearrangement reaction of chiral non-racemic allylic sulfides
作者:Andrew G.H Wee、Qing Shi、Zhongyi Wang、Kimberly Hatton
DOI:10.1016/s0957-4166(03)00079-x
日期:2003.4
The tandem sulfonium ylide formation-[2,3]-sigmatropic rearrangement reaction of chiral non-racemic secondary allylic sulfides, (E)-9 and (Z)-10, is found to proceed with high diastereocontrol. The C-5 stereocenter bearing the sulfide group is essential for high diastereoselectivity in the reaction. Transition state conformers are proposed to explain the high diastereoselectivity in the formation of
发现手性非外消旋仲烯丙基硫化物(E)-9和(Z)-10的串联t叶立德形成-[2,3]-σ重排反应在高非对映控制下进行。带有硫化物基团的C-5立体中心对于反应中的高非对映选择性至关重要。提出了过渡态构象异构体以解释非对映产物18a和18b的形成中的高非对映选择性。该方法适用于(R)-4-(4-氯苯基)-2-丁内酯。实现了适度的对映选择性(63%ee),这归因于第二烯丙基烯丙基硫化物22形成过程中的部分消旋作用。